1. Field of the Invention
The present invention relates to a camera system and more specifically, to a camera system provided with a plurality of selectable exposure lines or exposure modes.
2. Description of the Prior Art
U.S. Pat. Nos. 4,534,639 and 4,673,277 discloses such a camera system in which a plurality of AE modes are provided so as to correspond to various purposes in photography, and in which photometric mode is changed in response to a selected AE mode and judgment is made on whether or not the selection thereof is proper or not.
On the other hand, another camera system is disclosed in U.S. Pat. No. 4,358,188 in which a combination of an aperture value and a shutter speed value relative to a certain brightness value can be changed without changing the exposure amount by a predetermined amount. According to this camera system, when the shutter speed value and the aperture value to be changed have reached control limits of the camera respectively, further change is inhibited.
However, there are some cases where the combination of the aperture value and the shutter speed value determined in a certain AE mode should not be changed in order to achieve a certain purpose or to obtain a certain effect in photography. And, because such a change depends on the skill of a photography, it is not desirable to change the combination for an unskilled photographer, for example, a beginner.